The pukhraj stone is said to be ruled by Jupiter, the largest planet in the solar system. Hence, it is often called the most effective and powerful gem of them all. Jupiter rules the north-east and largely influences the cosmic events on Thursdays. Hence, Thursday is known to be Jupiter"s day, according to Vedic traditions. Sanskrit, the language in which most Vedic scripts and verses are written, refers to Thursday as Brihaspativar. Brihaspati is the Sanskrit name for Jupiter. Hence, Thursday is named after Jupiter.